植物证据在刑事案件侦破中的应用

法医植物学是研究与法律相关的植物证据问题的一门交叉学科,其研究主要涉及犯罪现场相关植物的分布、毒品原植物的鉴定以及植物的生长发育和变化规律等。作为犯罪现场中重要的生物学证据之一,大部分的植物证据分布广泛、个体微小且数量较多,有些种类的植物证据不易腐败,有些种类的植物证据易粘附在人体毛发或衣物上,因此与许多类型的刑事案件能够发生关联。在某些故意杀人、故意伤害、抢劫、入室盗窃、强奸、绑架、拐卖人口、毒品制造等刑事案件的侦破中,现场和嫌疑人员、被害人身上发现的植物证据可用于辅助推断作案地点、溺死落水地点,排查嫌疑作案车辆,鉴定毒品原植物种属及追溯其原产地,以及推断作案时间、死亡时间与埋尸时间等,具有良好的应用前景。本文对植物证据在刑事案件中的应用研究进行综述,并就其未来研究趋势作简要探讨。

植物证据在校园犯罪案件中的应用

本文以重庆某高校校园的植物为研究对象,经调查走访确定了该校园内的隐蔽路径,采集并研究校园内的开花植物和具有典型特征的叶片植物,运用扫描电子显微镜和体视显微镜对植物花粉和叶片进行外观形态观察,并以该校园为模型,制作了植物花粉区域性分布地图,初步建立了校园犯罪相关植物证据数据库,为将来刻画相关案件嫌疑人的行动轨迹、确定案发地点以及认定犯罪嫌疑人等方面提供有力辅助作用。

西周王朝早期的东方军事重镇:山东高青陈庄遗址的古植物证据

在我国悠久的历史长河中,西周王朝因其广封诸侯、扩大统治疆域而著称.山东地区号称"齐鲁之邦",即是源于西周初年分封的齐国和鲁国.然而,由于受到文献和考古资料的限制,这段历史中西周王朝经略东方、分封齐国的历史,却一直扑朔迷离.山东高青陈庄西周城址和车马坑、祭坛等重要遗迹及带铭文青铜器的发现,引起了学术界对西周王朝前期历史和齐国早期历史研究的强烈关注,其中的关键之一就是对该城址性质的认识.由于直接说明城址性质的材料有限,目前关于城址性质的认识存在严重分歧.保留在古代遗址中的植物遗存是研究遗址性质及功能的重要资料,陈庄遗址系统的植物考古研究显示,城址中保存了丰富的优良牧草草木樨属种子,结合车马坑等考古发现,我们推测这些草木樨属植物可能是战马的饲料,这一研究结果支持了陈庄城址可能是西周王朝早期东方军事城堡的观点.

生物演化过程中的突变性及其植物学证据

物种的形成过程并非遵循达尔文倡导的渐变论，而是当环境恶化时由祖先种通过自身的调节突然产生的。植物也可以因种间、属间或更高级分类单元间的杂交产生能繁育后代的新种，其过程无疑也是通过突变实现，对此本文暂不做深入讨论。在突变发生以后，生物的性状极少变化，为稳定期。古植物学中大叶系植物由无叶类演化到具大型羽状复叶的过程，有节类茎的纵脊在节上由直通到相错、叶由分叉到连合的过程；以及现代植物中的观音座莲从二次羽状复叶变为一次羽状复叶和车前草在南方种身上长出北方种的事实都证明了这一点。

Evidence That the Auxin Signaling Pathway Interacts with Plant Stress Response

Auxin influences a variety of developmental and physiological processes. Early reports, suggested that auxin might affect plant stress response. We have identified a number of auxin responsive genes in Arabidopsis thaliana (L.) Heynh. by using cDNA an-ay and found that stress responsive genes, such as,Arabidopsis homolog of MEK kinase 1 (ATMEKK1), ReL/SpoT homolog 3 ( At-RSH3), Catalase 1 ( Cat1) and Ferritin 1 (Fer1), were down-regulated by auxin, indicating that auxin regulates ale expression of stress responsive genes. We also demonstrated that nitrilase genes, nitrilase I ( NIT]) and nitrilase 2 (NIT2) involving in indole-3-acetic acid (IAA) biosynthesis, were induced by salinity stress, suggesting that the level of IAA might increase in response to salinity stress. To dissect the signal pathway involved in the interaction, two auxin insensitive mutants, auxin resistant 2 (axr2) and auxin resistant 1-3 (axrl-3) were used. Stress responsive genes were induced by salt stress in wild type and axr2, but not in axr1-3. The result suggests that die interaction between auxin and stress responses may be linked in the ubiquitin pathway.

Changes in phytoplankton communities along nutrient gradients in Lake Taihu:evidence for nutrient reduction strategies

An annual investigation on phytoplankton communities was conducted to reveal the effects of nutrients on phytoplankton assemblages in Lake Taihu,East China. A total of 78 phytoplankton taxa were identified. Phytoplankton biomass was higher in the northern part of the lake than in the southern part. Cyanobacteria and Bacillariophyta alternated dominance in the northern area,where algal blooms often appear,and co-dominated in the southern area. In the northern part,the proportions of cyanobacteria and Bacillariophyta varied significantly in total biovolume,both along the phosphorus(P) gradient,and between total nitrogen levels(≤3 mg/L and >3 mg/L TN). The proportions of cyanobacteria and Bacillariophyta had no signif icant variations in total biovolume along P and N(nitrogen) gradients in the southern part. Correlation analysis and CCA results revealed that P was the key factor regulating phytoplankton community structure. Nitrogen was also important for the phytoplankton distribution pattern. It was concluded that nutrient structure was heterogeneous in space and shaped the distribution pattern of phytoplankton in the lake. Both exogenous P and internally sourced Prelease needs to be considered. N reduction should be considered simultaneously with P control to efficiently reduce eutrophication and algal blooms.

Evidence for marine transgression between 7500–5400BC at the Luotuodun Site in Yixing,Jiangsu Province

Based on archaeological excavations, 217 samples were collected from the Luotuodun Site. Of them 63 samples from the section plane of the site layer were used for identification analysis of foraminifera, plant debris and seed fossils, and four samples were used for 14C dating and relevant analysis. Through many kinds of experiments, we have drawn some conclusions. Firstly, benthic foraminifera, such as Ammonia compressiuscula and Ammonia cff. sobrina, are found in the lOth layer, indicating that between 7500 and 5400 BC, i.e. before the emergence of the Majiabang Culture, Luotuodun Site and its nearby regions had ever experienced a marine transgression event. Secondly, we have found 450 plant fossils in this site, such as Polygonum sp., Scripus sp., Najas sp., Physalis sp., which indicated lacustrine or swamp environment.

Biomarker evidence for paleoenvironmental changes in the southern Yellow Sea over the last 8200 years

Previous studies have indicated that the Yellow Sea underwent significant environmental changes during the Holocene, but many questions remain concerning the timing of the establishment of the modern circulation system, which would have major implications for the Yellow Sea ecosystem and carbon cycle. In this study, marine and terrestrial biomarkers were analyzed in Core YE-2 from a muddy area in the southern Yellow Sea to reconstruct Holocene environmental and phytoplankton community change. The content of three individual marine phytoplankton biomarkers (alkenones, brassicasterol and dinosterol) all display a similar trend, and their total contents during the early Holocene (362 ng/g) were lower than those during the mid-late Holocene (991 ng/g). On the other hand, the contents of terrestrial biomarkers (C27+C29+C31n-alkanes) during the early Holocene (1 661 ng/g) were about three times higher than those during the mid-late Holocene (499 ng/g). Our biomarker results suggest that the modern circulation system of the Yellow Sea was established by 5-6 ka, and resulted in higher marine productivity and lower terrestrial organic matter inputs. Biomarker ratios were used to estimate shifts in phytoplankton community structure in response to mid-Holocene (5-6 ka) environmental changes in the Yellow Sea, revealing a transition from a dinoflagellate-diatom dominant community structure during the early Holocene to a coccolithophore-dominant community structure during the mid-late Holocene.

Late Holocene Environmental History of Lake Victoria Basin： Evidence from Geochemical Proxies

Sedimentary TOC （total organic carbon）, TN （total nitrogen） and C/N （carbon/nitrogen） at selected sites of Lake Victoria basin have provided evidence of phytoplankton productivity, input of nitrates and allochthonous （land） plant materials/catchment destruction in the basin during the late Holocene period （last 4,000 years to present）. TOC and TN in the sediment cores were determined using EuroEA3000 Series Elemental Analyser and radiocarbon dating done using AMS （accelerator mass spectrometry） standard method. Results showed that TOC （13.45%-20.78%） and TN （1.07%-1.92%） values were higher at Napoleon Gulf from about 4,186 years before present （ca. 4,186 yr. BP） to present than at inlet of river Kagera （TOC： 3.27%-6.32% and TN： 0.30%-0.59%） from about 190 years before present （ca. 190 yr. BP） to present. Generally TOC and TN had a negative correlation （r = -0.37, p = 0.04, n = 32） at Napoleon Gulf in the last 4,186 years to present signifying that C/N ratios were governed mostly by phytoplankton productivity which markedly increased during some periods in the last 370 years to present possibly as a result of increased input of nitrates. However, the periods from about 4,186 years to 1,684 years before present （ca. 4,186 yr. BP to 1,684 yr. BP） and some periods between the last 370 years to present indicated increased input of allochthonous plant materials/catchment destruction. On overall, there was a positive correlation between C/N and TOC at inlet of river Kagera （r = 0.57, p = 0.01, n = 20） in the last 190 years to present possibly signifying that C/N ratios were governed mainly by input of allochthonous plant materials hence increased catchment destruction. Input of land plant materials （catchment destruction） along Kagera basin declined during some period after 1950 AD. However the most recent years have shown increased input of land plant materials （catchment destruction） in Kagera basin.

Scientists Use Palaeobotanical Evidence to Estimate Early Miocene Elevation in Northern Tibet

The area and elevation of the Tibetan Plateau over time has directly affected Asia’s topography,the characteristics of the Asian monsoon,and modified global climate—but in ways that are poorly understood.Charting the uplift history is crucial for understanding the mechanisms that link elevation and climate irrespective of time and place.While some palaeoelevation data are available for southern and central Tibet,clues to the uplift history of northern Tibet remain sparse and largely circumstantial.Lately,

Stable carbon and nitrogen isotope evidence of human and pig diets at the Qinglongquan site,China

Previous studies on the Rice-Millet （foxtail millet and common millet） Blended Zone in Chinese Neolithic have not clearly addressed such questions as the importance of primitive rice-millet mixed agriculture to human lifestyle and livestock managements within this region, the relationship among the development of the agriculture, paleoenvironment, and cultural interactions, and so on. Here stable carbon and nitrogen isotope analysis of human and pig bones from the Qinglongquan site was conducted, covering two cultural phases, namely the Qujialing Culture （3000 BC to 2600 BC） and the Shijiahe Culture （2600 BC to 2200 BC）. Based on this analysis, we further discussed the diets of ancient humans and pigs in the site, investigated the importance of rice-millet mixed agriculture to human and pig diets, and explored the relationship among the primitive rice agriculture and millet agriculture, cultural interactions, and paleoenvironment. The δ^13C values of human bone collagen （-16.7‰ to -12.4‰, averaging -14.6‰±1.3‰, n=24） revealed that both C3 and Ca foods were consumed, probably from the contribution of rice （C3 plant） and millets （C4 plants） due to the coexistence of these crops at this site. In addition, the human mean δ^13C value suggested that millet agriculture was only minor in human diets. The human δ^15N values （6.6‰ to 10.8‰, averaging 9.0‰±1.2‰, n=24） showed that animal resources played a significant role in human diets, and varied greatly. The mean δ^13C value of the pigs （-14.3‰±2.5‰, n=13） was quite similar to that of the humans, but the mean δ^15N value of the pigs was slightly less （1.3‰） The similar δ^13C and δ^15N values between humans and pigs suggested that the pigs consumed a lot of humans＇ food remains. No correlations of the δ^13C and δ^15N values between humans and pigs showed that both human and pig diets were based mainly on plant foods, which might be related to highly developed rice-millet mixed agriculture at that time. In comparison with the human and pig diets between the two periods, millet agriculture contributed more than 10% in the Shijiahe Culture, if a simple mixing model was used. This apparent dietary shift matched the climatic variation and agricultural development through the time. In warm and humid climate with the expansion of the Qujialing Culture northwards, rice was widely cultivated. However, when the climate was cold and add, northern culture was expanding southwards. Thus, millet agriculture became more important.

First record of extinct fruit genus Chaneya in low-latitude tropic of South China

Fossil reproductive structure from the Eocene of the Changchang Basin (Hainan Island,South China) is recognized as Chaneya hainanensis sp.nov.This new species is characterized by persistent corolla of five obovate petals with three subparallel primary venation linked by arching secondary veins,circular central disk bearing two orbicular ovaries or fruit bodies.This discovery confirms the presence of the extinct fruit genus Chaneya in low-latitude tropical area,providing significant fossil evidence for investigating the origin,migration,and phytogeography of this genus and discussing the Tertiary floristic exchanges among North America,eastern Asia,and Europe.Considering the distribution of this genus and its extant relatives and the climate changes during the Cenozoic,we hypothesize that Chaneya was a widespread tropical or subtropical taxon,but,with climate cooling,became extinct in northern latitudes and evolved into Picrasma (Simaroubaceae) and Rutaceae mainly in modern tropics and subtropics.

Trend of Santonian (Late Cretaceous) atmospheric CO_2 and global mean land surface temperature: Evidence from plant fossils

Quantitative reconstructions of atmospheric CO2 by using terrestrial and marine records are critical for understanding the so-called ＂greenhouse＂ conditions in the Cretaceous, but data from terrestrial plants for several stages of this period remain quite limited. Using the stomatal index （SI） technique, here we estimate the Santonian （Late Cretaceous） CO2 contents based on a sequence of fossil cuticles of Ginkgo adiantoides （Ung.） Heer from three beds of the Yong＇ancun Formation in Jiayin, Heilongjiang Province, northeastern China. By the regress function, Sis of Ginkgo fossils reveal a pronounced CO2 reduction from the early to late Santonian （-661 and -565 ppm, respectively）. The relatively high CO2 levels provide additional evidence for paleoclimatic warmth in this interval. Moreover, available paleobotanical data illustrate a decline trend of CO2 contents throughout the Late Cretaceous, punctuated by several fluctuations in particular episodes with different magnitudes. The CO2 contents shifted notably in the late Cenomanian, Turonian, early Santonian, late Campanian, and probably latest Maastrichtian. Furthermore, a comprehensive study based on CO2 data shows that the global mean land surface temperature （GMLST） fluctuated several times accordingly. The change ratios of GMLST （AT） increased from -3℃ in late Cenomanian to -4.7℃ in mid Turonian, and then dramatically reduced to -2.2℃ in mid Coniacian. From the Santonian onward, it appears that the temperature gradually decreased with a few minor fluctuations.